Following his PhD, Hunt returned to New York to work with London, in collaboration with Nechama Kosower, her husband Edward Kosower, and Ellie Ehrenfeld. While there, they discovered that tiny amounts of glutathione inhibited protein synthesis in reticulocytes and that tiny amounts of RNA killed the synthesis altogether. After returning to Cambridge, he again began work with Tony Hunter and Richard Jackson, who had discovered the RNA strand used to start haemoglobin synthesis. After 3–4 years, the team discovered at least two other chemicals acting as inhibitors.[14]

Hunt regularly spent summers working at the Marine Biological Laboratory at Woods Hole, Massachusetts, which was popular with scientists for its advanced summer courses, and in particular, with those interested in the study of mitosis. The location provided a ready supply of surf clams and sea urchins amongst the reefs and fishing docks, and it was these invertebrates that were particularly useful for the study of the synthesis of proteins in embryogenesis, as the embryos were simply generated with the application of filtered sea water, and the transparency of the embryo cells was well suited to microscopic study.[20]

It was there at Woods Hole in the Summer of 1982 using the sea urchin (Arbacia punctulata) egg as his model organism, he discovered the cyclin molecule.[14] Hunt was a keen cyclist and named the protein based on his observation of the cyclical changes in its levels.[21]

Cyclins are proteins that play a key role in regulating the cell-division cycle.[22] Hunt found that cyclins begin to be synthesised after the eggs are fertilised and increase in levels during interphase, until they drop very quickly in the middle of mitosis in each cell division. He also found that cyclins are present in vertebrate cells, where they also regulate the cell cycle. He and others subsequently showed that cyclins bind and activate a family of protein kinases, now called the cyclin-dependent kinases, one of which had been identified as a crucial cell cycle regulator by Paul Nurse. The cyclin mechanism of cell division is fundamental to all living organisms (excluding bacteria) and thus the study of the process in simple organisms helps shed light on the growth of tumours in humans.[23]

Distinguished for his studies of the control of protein synthesis in animal cells and for the discovery of cyclin, a protein which regulates the eukaryotic cell cycle. Together with Jackson and their students, he defined steps in formation of the initiation complex in protein synthesis, showing that the 40S ribosomal subunit binds initiator tRNA before it binds mRNA, and that this step was the target of inhibitors such as double-stranded RNA or haem deficiency. They showed that inhibition of protein synthesis is mediated by reversible phosphorylation of initiation factor eIF-2 by two distinct protein kinases and they elucidated the unexpected roles of thioredoxin and thioredoxin reductase in protein synthesis. With Ruderman and Rosenthal, he demonstrated selective translational control of mRNA in early clam embryos. This led to Hunt's discovery of cyclin as a protein which is selectively destroyed in mitosis. He subsequently cloned and sequenced cyclin cDNA from sea urchins and frogs and showed by elegant mRNA ablation experiments that cyclin translation is necessary for mitosis in frog embryos. He has also shown that cyclin is a subunit of the mitosis-promoting factor which regulates entry into mitosis. His discovery and characterization of cyclin are major contributions to our knowledge of cell cycle regulation in eukaryotic cells.

is awarded for his discovery of cyclins, proteins that regulate the CDK function. He showed that cyclins are degraded periodically at each cell division, a mechanism proved to be of general importance for cell cycle control.[32]

In 2003, Hunt was made an honorary Fellow of the Royal Society of Edinburgh (HonFRSE).[4] In 2006, he was awarded the Royal Society's Royal Medal, two of which are presented annually for "the most important contributions to the advancement of natural knowledge", in his case for "discovering a key aspect of cell cycle control, the protein cyclin which is a component of cyclin dependent kinases, demonstrating his ability to grasp the significance of the result outside his immediate sphere of interest".[33]

Hunt was knighted in the 2006 Birthday Honours, but has said that he rarely uses the title 'Sir' and that it should not affect his scientific standing.[34]

Hunt is married to Mary Collins, who was also educated at the University of Cambridge. The couple have two daughters.[1]

Collins is a professor of immunology. In the summer 2016, she was appointed director of research at the newly founded Okinawa Institute of Science and Technology, and the couple moved to Japan for an extended stay expected to last five years.[36]

On 8 June 2015, during the 2015 WCSJ, at a lunch for female journalists and scientists, Hunt was asked on short notice to give a toast. Hunt's impromptu speech was later recounted by an unnamed EU official:[37][38][39]

It's strange that such a chauvinist monster like me has been asked to speak to women scientists. Let me tell you about my trouble with girls. Three things happen when they are in the lab: you fall in love with them, they fall in love with you, and when you criticise them they cry. Perhaps we should make separate labs for boys and girls? Now, seriously, I'm impressed by the economic development of Korea. And women scientists played, without doubt an important role in it. Science needs women, and you should do science, despite all the obstacles, and despite monsters like me.

A short recording was made at the event by Natalia Demina. In it, Hunt said:[40][37]

So, congratulations, everybody, and I hope – I hope – I hope – I really do hope there is nothing holding you back, especially not monsters like me.

In the recording, one can hear Hunt's concluding remarks being followed by a very brief piece of laughter and applause before the recording ends.[41]

A member of the audience, Connie St Louis, tweeted her recollection of parts of this speech on 8 June. These comments without context were widely re-tweeted, but not until a day later, on 9 June; they were then condemned in a reaction that The Observer described as a "particularly vicious social media campaign",[42] Hunt being subject to "intense, vitriolic online abuse".[43] A number of women scientists responded by posting photographs of themselves at work using the hashtag #distractinglysexy.[44]

That same day the Royal Society formally distanced itself from Hunt's comments as reported and emphasised its commitment to equality in the sciences.[45][46]

Two days later, 10 June, Hunt gave an interview to BBC Radio 4's Today programme,[47] in which he said "I did mean the part about having trouble with girls. It is true that I have fallen in love with people in the lab, and that people in the lab have fallen in love with me, and it’s very disruptive to the science. It’s terribly important that, in the lab, people are on a level playing field. And I found these emotional entanglements made life very difficult. I mean, I’m really, really sorry that I caused any offence – that’s awful. I certainly didn’t mean – I just meant to be honest, actually."[48] Hunt went on to say "I'm very sorry if people took offence. I certainly did not mean to demean women, but rather be honest about my own shortcomings."[42][49]

Numerous media outlets reported on the incident and the BBC interview, citing portions of Hunt's original remarks and criticising them as sexist.[50][51] Science journalist Connie St Louis gave 37 words of the remark (from "Let me tell you about my trouble with girls" to "when you criticise them they cry") but said "he just ploughed on for about five to seven minutes."[52]

Hunt felt he had made it clear he was joking because he had included the phrase "now seriously" in his statement.[53] The reconstruction of his words by an unnamed EU official corroborated the inclusion of these words.[54] On 27 June, The Times reported that St Louis had, contrary to some of the previous statements, accepted that Hunt's comments were made "in jest".[55] It was only on 18 July, 39 days after Hunt's comments, that the recording of part of them (and the laughter and applause) became public.[41]

On 10 June Hunt resigned from his position as an honorary professor with the University College London's Faculty of Life Sciences[56] and from the Royal Society's Biological Sciences Awards Committee.[57] Hunt's wife, immunologist Mary Collins, had been told by a senior [at UCL] that Hunt "had to resign immediately or be sacked".[42] A European Commission politician called Sir Tim and demanded he resign his European Research Council post. Internal ERC documents show deep unhappiness within the scientific council at this interference. Hunt was invited to the ERC's farewell dinner for all its retiring members in November, where Prof. Dame Athene Donald stated he received a "warm welcome". Several female scientists and commentators defended Hunt. DameAthene Donald, ERC, a physicist who is President of the British Science Association, Master of Churchill College, Cambridge and a fellow of the Royal Society, said Hunt "was always immensely supportive of the ERC’s work around gender equality".[42]

The decision to ask Hunt to resign from his honorary position at UCL was taken without consultation with the council, the university's governing body.[58] The UCL president, Michael Arthur, released a statement, reported on the BBC on 26 June, stating that there would be no reinstatement of Hunt, as it would send "entirely the wrong signal".[59] The university's council later confirmed this decision.[60] However, in July, Hunt was reappointed by the Royal Society to represent them on a working group on European funding. The report was released in December, and a Royal Society spokesman said that Hunt was "a leading expert" and "a natural choice".

On 30 June, The Guardian reported that broadcaster Jonathan Dimbleby had resigned from an honorary fellowship at UCL in protest at its treatment of Hunt.[61] Also, author and journalist Jeremy Hornsby wrote University College London out of his will in protest, leaving it "about £100,000 worse off".[62]

At least 8 Nobel prizewinning scientists and 21 honorary fellows had criticised the treatment of Hunt following his resignation, while a few scientists, such as Hunt's co-Nobelist were critical of Hunt's conduct and agreed his resignation was warranted.[63][64]Boris Johnson,[65] the mayor of London, and Richard Dawkins[38] also expressed their indignation at the treatment of Hunt.

Imran Khan, Chief Executive of the British Science Association, speaking to the BBC, described Hunt's comments as "careless", adding that it is "hard to find Sir Tim's comments funny if you've been held back by systemic bias for years – whether those remarks were intended as a joke or not".[48] British neuropsychologist Dorothy Bishop, while noting Hunt's being described as a "decent human being" by most of the women who knew him, noted that he had still "set back the cause of women in science" and should not sit on any Royal Society committee involved in making decisions about fellowships, prizes or policy.[66]

Physicist and broadcaster Brian Cox, speaking on BBC Radio 4's The World at One, described Hunt's comments as "very ill-advised", but criticised what he saw as the hounding out of Hunt as a disproportionate response to concerns over his comments and part of a "wider problem of trial by social media".[67]

In a letter to The Times a group of 29 staff scientists, students and postdoctoral fellows, both male and female, who had worked with Hunt, wrote in support of his character. They described how his help had been "instrumental in the advancement of many other women and men in science beyond those in his own lab" and how he had "actively encouraged an interest in science in schoolchildren and young scientists, arranging for work experience and summer students of both genders to get their first taste of research in his lab". They urged the ERC and UCL to "reconsider their rush to judgment".[68][69]

Paul Nurse, head of the Royal Society, who shared the 2001 Nobel prize in medicine with Hunt, while stressing his esteem for Hunt as a person, originally stated that Hunt had said "some stupid things which cannot be supported and they had to be condemned" and that the affair had been bad for science and for the Royal Society in particular, adding that the discussion had "become totally polarised with extreme views on both sides".[64] In a later statement, Nurse described the response to Hunt's comments as "a twitter and media storm, completely out of proportion", adding that "he should never have been sacked by University College London".[71]

In October 2015, Sir Colin Blakemore resigned as honorary president of the Association of British Science Writers (ABSW) in protest over its decision to support the claims made by Connie St Louis. He maintains that her account was "unbalanced, exaggerated, and selective" and criticises the ABSW's decision not to investigate the issue. Blakemore's position was backed by Athene Donald, who had written to the ABSW, asking them to investigate the way the story was reported, writing that "Tim Hunt's reputation has been destroyed because careful journalistic due diligence was not followed by many who wrote about the event, and the ABSW decision not to take any further action appears to endorse such behaviour." ABSW president Martin Ince replied that the association's statement had simply supported St Louis's "right to report a story without fear of personal attack", stating that Hunt had "acknowledged the accuracy of St Louis’s reporting".[43] However, it later emerged that Hunt had said her reporting of his toast was "quite inaccurate, and very selective".[72]

One unnamed female scientist who had been critical of Hunt said that she had been subjected to "a torrent of abuse" on social media and that it was "not worth the aggro of waking up to calls for me to be sacked".[73] For his part, Hunt has distanced himself from the controversy, commenting that he had been "turned into a straw man that one lot loves to love and the other lot loves to hate and then they just take up sides and hurled utterly vile abuse at everyone".[74]

^Cathy Young (22 July 2015). ""Sexist Scientist" Tim Hunt: The Real Story". Real Clear Politics. On July 18, The Times published a new bombshell: a 12-second recording of the final moments of Hunt’s remarks that Demina had discovered among her materials from the conference and turned over to the newspaper with Mensch’s help.Missing or empty |url= (help)

^"Sir Tim Hunt FRS and UCL". UCL. 10 June 2015. Archived from the original on 16 June 2015. UCL was the first university in England to admit women students on equal terms to men, and the university believes that this outcome is compatible with our commitment to gender equality.